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Sending humans to the moon and Mars in support of NASA’s Vision for Space Exploration (VSE) presents a variety of operational environments in which astronauts will need to wear a space suit, both inside the vehicle and during Extravehicular Activity (EVA). Four feasible suit architectures were proposed by NASA in terms of the number and type of suits needed to enable task performance in scenarios ranging from launch and entry operations to conducting EVA’s in microgravity and on planetary surfaces. This study was aimed at defining space suit operational and functional needs across the spectrum of mission elements called out in the VSE, identifying temporal and technical design drivers, and establishing appropriate trade variables with associated weighting factors for analyzing the proposed architecture options. Recommendations from the analysis are offered for consideration in selecting from the four options.

Rotordynamics developed from the beginning of the 20th century to deal with problems associated with steam turbines. This paper deals with intense developments starting around 1975 through 2000 in rotordynamics to deal with new, larger machines running at higher speeds and higher power levels. Most of the new problems of interest dealt with subsynchronous instabilities. Issues associated with “synchromnously unstable” motion due to the Morton Effect is also reviewed.